Cell division is a fundamental piece of information about cell movement. Cell division and the formation of scaffolding are typically thought to be related, and a more normal growth rate can be maintained by a group of cells gathered together than by a cell that exists in isolation. Depending on the cell, a growth factor such as PDGF (platelet-derived growth factor) is sometimes secreted to control the growth of the other cells in the group (e.g., see Non-patent Document 1). Cell growth is thus controlled by social interaction.
Conventionally, states in which cells are grown or inhibited as described above are determined by using a microscope to observe a cell at regular time intervals, capturing a plurality of microscopically observed images, and assessing these captured images. For example, binary observation is used to determine that a state in which cells have bound together into a colony upon being observed indicates a cell-behavior-induced change from individual cells to a colony of cells.
Non-patent Document 1: Albert, Bruce et al., K. Nakamura and K. Matsubara tr., Molecular Biology of the Cell, 2nd ed., Tokyo: Newton Press, November 1993, pp. 748-749, pp. 1188-1189.